Related papers: Composite Scalars at LEP: Constraining Technicolor…
We study the sensitivity of LEP II and NLC, via two photon collisions, to the effects of anomalous $\tau \overline{\tau} \gamma$ couplings. We also discuss some CP-odd observables that can be useful to disentangle the contributions from the…
It is possible to place direct constraints on WW-photon and WWZ couplings by studying their tree-level contributions to the process e^+e^- ---> W^+W^-. However, these couplings also contribute at the loop level to e^+e^- ---> f fbar…
Normal broadband lasers with collinear polychromatic components have immense potential for mitigating laser plasma instabilities (LPIs). However, the projection complexity of collinear polychromatic light (CPL) is a significant challenge…
Using the experimental values for the rates $R^{LEP} _{exp}=\Gamma_{inv}/\Gamma_{l\bar l}=5.942\pm 0.016$, $R^{Giga-Z_1}=\Gamma_{inv}/\Gamma_{l\bar l}=5.942\pm 0.012$ (most conservative) and $R^{Giga-Z_1}=\Gamma_{inv}/\Gamma_{l\bar…
In this paper we calculate the contributions to the branching ratio of $B\to X_s \gamma$ from the charged Pseudo-Goldstone bosons appeared in one generation Technicolor model. The current $CLEO$ experimental results can eliminate large part…
Photoassociation (PA) of ultracold metastable helium to the 2s2p manifold is theoretically investigated using a non-perturbative close-coupled treatment in which the laser coupling is evaluated without assuming the dipole approximation. The…
The high statistics of the combined LEP lineshape data are used to derive constraints on hypothetical extensions of the Minimal Standard Model. The data comprises about eight million visible Z decays, recorded between 1989 and 1993. This…
Upper bounds at the weak scale are obtained for all $\lambda_{ij}\lambda_{im}$ type product couplings of the scalar leptoquark model which may affect K-K(bar), B_d-B_d(bar), and B_s-B_s(bar)$ mixing, as well as leptonic and semileptonic K…
The recent detection of the cosmic microwave background polarimeter experiment BICEP2 of tensor fluctuations in the B-mode power spectrum basically excludes all plausible axion models where its decay constant is above $10^{13}$ GeV.…
We study the impact of LEP2 constraints on the dimensionless coefficients of the electroweak chiral Lagrangian on the precision observables using the improved renormalization group equations. We find that the current uncertainty in the…
Recent study on the charged top-pion correction to R_b shows that it is negative and large, so that the precision experimental value of R_b gives rise to a severe constraint on the topcolor-assisted technicolor models such that the top-pion…
The new precise LEP measurements of alphas and the electroweak mixing angle as well as the new LEP II mass limits for supersymmetric particles and new calculations for the radiative (penguin) decay of the b-quark into sgamma allow a further…
New strong gauge interactions remain a viable source for the electroweak symmetry breaking. However, addressing the generation of fermion masses remains a challenge. A basic observable which provides stringent constraints on the flavor…
The production of invisible pairs of lightest neutralinos accompanied by a large-angle hard photon in the reaction $e^+ e^- \to \chi^0_1 \chi^0_1 \gamma$ is studied at LEP2 energies. The most general gaugino/higgsino composition of the…
We present an effective Lagrangian for low-scale technicolor. It describes the interactions at energies near the mass of the lowest-lying bound states of the lightest technifermion doublet -- the spin-one $\rho_T,\omega_T, a_T, f_T$ and the…
Studies of axion-like particles (ALPs) commonly focus on a single type of interaction, for example couplings only to photons. Most ALP models however predict correlations between different couplings, which change the phenomenology in…
During the LEP2 period the e+e- collider increased its center of mass energy from 161 GeV to 209 GeV and a total integrated luminosity of approximately 700 pb-1 was recorded per experiment. Pairs of W bosons are produced and allow the study…
The interplay of spectroscopy, scaling laws and critical indices is studied in strongly coupled quenched QED. Interpreted as a model of technicolor having strong interactions at short distances, we predict the techni-meson mass spectrum in…
Simple models are proposed where the baryon and lepton number are gauged and spontaneously broken near the weak scale. The models use a fourth generation that is vector-like with respect to the strong, weak and electromagnetic interactions…
It has been commonly assumed that pseudoscalar contributions to the leptonic decay of charged mesons, like pions and kaons, is strongly constrained due to the helicity suppression present in the ratio $R_{l/l'} = \Gamma(P \rightarrow…